I am very familiar with what you are talking about. My first Dexta was so worn out, after it got warm, and revved over 1600, it would run away. Got tired of that, and when I tore it down for a rebuild, the rings fell apart like shelled corn. Was surprised it even ran.
On this one, I blew out the cylinders with air as I cranked it and put oil drops, let that permeate and then pull started it. It ran and the exhaust was crisp, then ran out of fuel.
The primer bulb, bottom tank valve was bad. Replaced. Ready to pull start it again.
Just pulled in last night with another Super Dexta. Ok, 4:30 this morning. This one has some unique features, especially chrome. Fully complete with the exception, the trailer bar is missing. Its not locked up, and I'm optimistic it will be running this weekend. Tin is hardly dented.
Went to the FNH dealer to get a fuel filter, and was reminded Dextas are antiques. They're older than I am, said the parts guy. You're the first guy I've ever asked for a Dexta part (He's new there...) $28. fot the filter. I can see why I told him, that filter is 3 times the cost. Went to Advanced Auto, and got it for $8.25 with tax.